defmodule EVM do
  @moduledoc """
  Documentation for EVM.
  """

  @type account :: %{                                  #σ[a]
    :nonce => integer(),                               #σ[a]n
    :balance => integer(),                             #σ[a]b
    :storage => MerklePatriciaTree.Trie.t,             #σ[a]s
    :code => binary(),                                 #σ[a]c
  }
  @type world_state :: %{                               # σ
    binary() => account()
  }
  @type trie_root :: MerklePatriciaTree.Trie.root_hash
  @type val :: integer()
  @type address :: <<_::160>>
  @type hash :: <<_::256>>
  @type timestamp :: integer()

  @word_size_in_bytes 4
  @byte_size 8
  @int_size 256
  @max_int round(:math.pow(2, @int_size))

  @doc """
  Returns maximum allowed integer size.
  """
  def max_int(), do: @max_int
  def int_size(), do: @int_size
  def byte_size(), do: @byte_size

  @doc """
  Returns word size in bits.
  """
  def word_size(), do: @word_size_in_bytes * @byte_size
end